<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <!--[if lt IE 9]>
      <script src="https://cdn.jsdelivr.net/npm/html5shiv@3.7.3/dist/html5shiv.min.js"></script>
      <script src="https://cdn.jsdelivr.net/npm/respond.js@1.4.2/dest/respond.min.js"></script>
    <![endif]-->
    <title>Document</title>
    <!-- 一定不要忘记引入bootstrap的样式文件 -->
    <link rel="stylesheet" href="../04-Bootstrap/bootstrap/css/bootstrap.min.css">
    <style>
        /* 利用我们自己写的样式覆盖原先的样式 */
        
        .login {
            width: 80px;
            height: 45px;
        }
    </style>
</head>

<body>
    <button type="button" class="btn btn-success">（成功）Success</button>
    <div class="btn btn-success login">登录</div>
    <div class="btn btn-danger">未成功</div>
</body>

</html>